Vacuum probe surface sampler

ABSTRACT

A vacuum probe surface sampler for rapidly sampling relatively large surface areas which possess relatively light loading densities of micro-organisms, drug particles or the like. A vacuum head having a hollow handle connected to a suitable vacuum source is frictionally attached to a cone assembly terminating in a flared tip adapted to be passed over the surface to be sampled. A fine mesh screen carried by the vacuum head provides support for a membrane filter which collects the microorganisms or other particles with the head assembly being easily removed from the cone assembly without contacting the cone assembly with human hands.

1451 July 31, 1973 VACUUM PROBE SURFACE SAMPLER [76] Inventors: James C.Fletcher, Administrator of the National Aeronautics and SpaceAdministration with respect to an invention of; Bruce A. Zahlava, Cary,N.C.

[22] Filed: Dec. 30, 1971 [21] Appl. No.: 214,086

11/1971 Principe et al 73/42S.6 X 12/1961 Weiss 73/421 R X PrimaryExaminer-Richard C. Queisser Assistant Examiner-Daniel M. YasichAttorney.lohn R. Manning et al.

[57] ABSTRACT A vacuum probe surface sampler for rapidly samplingrelatively large surface areas which possess relatively light loadingdensities of micro-organisms, drug particles or the like. A vacuum headhaving a hollow handle connected to a suitable vacuum source isfrictionally attached to a cone assembly terminating in a flared tipadapted to be passed over the surface to be sampled. A fine mesh screencarried by the vacuum head provides support for a membrane filter whichcollects the microorganisms or other particles with the head assemblybeing easily removed from the cone assembly without contacting the coneassembly with human hands.

6 Claims, 4 Drawing Figures PAIENTED 3. 748. 905

sum 1 [IF 2 INVENTOR. BRUCE A. ZAHLAVA ATTORNEYS PAIENIED M3 1 3. 748905 SHEET 2 0F 2 VACUUM SOURCE INVENTOR. BRUCE A. ZAHLAVA ATTORNEYSVACUUM PROBE SURFACE SAMPLER ORIGIN OF THE INVENTION The inventiondescribed herein was made in the performance of work under a NASAcontract and is subject to the provisions of Section 305 of the NationalAeronautics and Space Act of 1958, Public Law 85-568 (72 Stat. 435; 42USC 2457).

BACKGROUND OF THE INVENTION This invention relates generally to asurface sampler and relates in particular to a vacuum probe surfacesampler having the capabilities of rapidly sampling relatively lightloading densities of micro-organisms, drug particles, or the like.

In the field of space exploration a definite need has arisen for aportable, lightweight, inexpensive sampling device to sample the surfaceof spacecraft returning from space missions for microorganisms or thelike. Also there is a need for a sampling device of this type, bylaw-enforcement officers, to check large areas of auto seats, bedcovers, clothing, etc., for illegal drug particles, and the like. To beeffective for this type of sampletaking, the sampler device must becapable of sterilization prior to use and free from external contam-'ination by contact with human hands prior to and subsequent to samplingof a suspect surface area.

It is therefore an object of the present invention to provide a new andnovel portable, lightweight, inexpensive surface sampler device.

Another object of thepresent invention is a surface sampler that has thecapabilities of sampling large surface areas which possess relativelylight loading densities of micro-organisms, drug particles or the like.

A further object of the present invention is a surface sampler that canbe operated by semi-skilled technicians and without danger ofcontaminating the test results by contact with human hands.

An additional object of the present invention is a vacuum probe surfacesampler having separable sterilizable parts that may be readilyassembled and dissembled without danger of contamination by human hands.

BRIEF SUMMARY OF THE INVENTION According to the present invention, theforegoing and other objects are attained by providing a cupshaped vacuumhead assembly having an integrally attached tubular handle adapted to begrasped by an operator and attachable to a suitable vacuum source. Afine mesh screen is retained in the head assembly by a suitable splitring and the entire head assembly frictionally fitted into the open endof a cone assembly. An elongated spout extends from the cone assemblyand terminates in a flared open tip for engaging the surface to besampled. The open end of the cone assembly receiving the head assemblyis in the form of a circular tripod with the tripod ends being spaced120 apart.

DETAILED DESCRIPTION OF THE INVENTION A more complete appreciation ofthe invention and many of the attendant advantages thereof will bereadily appreciated as the same becomes better understood by referenceto the following detailed description when considered in connection withthe accompanying drawings wherein:

FIG. 1 is a part section view of the assembled vacuum probe surfacesampler according to the present invention;

FIG. 2 is an exploded view of the vacuum probe surface sampler accordingto the present invention;

FIG. 3 is a view of the surface sampler of the present invention inoperation; and

FIG. 4 is a view illustrating the disassembly of the surface samplerafter completion of a sampling operation.

Referring now to the drawings, wherein like reference numerals designateidentical parts throughout the several views, and more particularly toFIGS. 1 and 2, there is shown the vacuum probe surface sampler accordingto the present invention and designated generally by reference numeral10. Surface sampler 10 is composed of two major parts, a head assembly12 and a cone assembly 22.

Head assembly 12 is essentially cup-shaped and is provided with anintegrally attached elongated tubular handle 14 as will be furtherexplained hereinafter. The rim at the open end of assembly 12 isprovided with a circumferential groove 16 for receiving a fine meshscreen 17. A split ring 18 serves to retain screen 17 within groove 16.Screen 17 may be formed of any conventional screening material with aIOO-mesh, .010- inch thickness stainless steel screen as support formembrane filter 43 (FIG. 2) which is suitable for retaining mostmicro-organisms. Membrane filtersof this type 'are' commerciallyavailable in a wide range of mean flow pour sizes, from A (7.5mp.) to5;].. A specific example membrane suitable for use in the presentinvention is Triacetate Metricel, Type GA-6 having a pour size of 0.45p. and a product of the Gelman Instrument Company, 600 S. Wagner Road,Ann Arbor, Michigan 48106. An O-ring seal 19 serves to insure a sealbetween vacuum head 12 and cone assembly 22.

Cone assembly 22 includes a hollow frusto-conical segment 23 having anintegrally attached cup-shaped base portion 24 having a scalloped rimarea forming a tripod with the scalloped tips being essentially I20apart and designated by reference numerals 26, 27 and 28 (FIG. 2). Acircumferential groove 29 is formed between conical segment 23 and thecup-shaped base 24 to receive O-ring 19 and, along with the taperedcomplimentary surfaces of the mated parts, serves to provide frictionalengagement of head assembly 12 by the cup-shaped base 24. A notched area31 (FIG. 3) is also provided within cup-shaped base 24 to receivetubular handle 14 in such position that the entire head assembly 12 isvertically spaced from the scalloped surfaces 26, 27 and 28 when thesurface sampler is assembled. An elongated tubular spout 34 alsointegrally extends from frusto-conical segment 23 and terminates in asubstantially flattened open tip portion 35. A pairof short leg members37 and 38 integrally extend from the opposite side of tip portion 35 toengage the surface area being sampled while maintaining the majorportion of tip 35 slightly spaced from the surface.

OPERATION The operation of theinvention is now believed apparent.Initially, vacuum head assembly 12 is assembled with screen 17 beingretained in place by split ring 18.. O-ring seal 19 is then positionedwithin groove 29and head assembly 12 and cone assembly 22 frictionallyjoined together. The entire cone assembly 22 is then sterilized in anyconventional manner prior to use thereof and can be packaged andmaintained until ready for use. When using the surface sampler 10,tubular handle 14 is connected to a suitable vacuum source 40 viaflexible tubing 41 (FIG. 3) and tip 35 moved over the surface to besampled by movement of handle 14. The vacuum source 40 will insure aflow of air through tip 35 as noted by the arrows in FIG, 3 and anymicro-organisms, drug particles or the like on the test surface flowingwith the air and trapped by membrane filter 43. After completion of asampling operation vacuum probe is disconnected from vacuum source 40and inverted as shown in FIG. 4. A slight tap to the protruding legs 26,27 and 28 on a table 42, or the like, will release cone assembly 22 fromhead assembly 12, leaving filter 43 in cone assembly 22-for easy removaland subsequent analysis of the trapped particles.

Although the invention has been described relative to a specificembodiment thereof, it is not so limited, and many modifications andvariations thereof will be readily apparent to those skilled in the artin the light of the above teachings. For example, no specific materialshave been described for making the various components, it beingunderstood that any suitable lightweight metal, plastics or the like,may be employed that would be inert to the material or harmless to themicroorganisms being sampled. The low cost of molding the cone assembly22 from plastics permits discarding or disposing of the unit after usethereby resulting in significant economics over cleaning, inspection,repair, packaging and're-sterilization. Also, although a specific filterscreen has been disclosed, it is to be understood that any conventionalscreen mesh size and screen material may be used with the presentinvention to provide support for membrane filter 43. Additionally, nospecific vacuum pressure has been disclosed and any conventional vacuumsystem may be employed with the test that will cause an even steady flowof air through the sampler so that the micro-organisms or otherparticles tested will be trapped by the filter screen. It is thereforeto be understood that within the scope of the appended claims theinvention may be practiced otherwise than as specifically described.

What is claimed as new and desired to be secured by Letters Patent ofthe United States is:

1. A vacuum probe surface sampler comprising: l. a head assembly,

a. said head assembly being cup-shaped and including an integrallyattached elongated tubular elongated tubular handle adapted to begrasped by an operator,

1. said tubular handle being connected to a vacuum source for operationof said surface samler,. II. a cine assembly detachably receiving saidhead assembly,

a. said cone assembly including a hollow frustoconical segment having anintegrally attached cup-shaped base portion and an elongated tubularspout,

l. said cup-shaped base portion having a periphery thereof in the formof a tripod,

2. said cup-shaped base portion also serving to receive said headassembly with a notched area in said cup-shaped base portion receivingsaid tubular handle in such position that when said head assembly isreceived by said cup-shaped base portion that the entire head assemblywill be vertically spaced from the tripod periphery of said cup-shapedportion,

3. said tubular spout terminating in a substantially flattened open tipportion,

4. a pair of leg members integral with said tip portion and adapted toengage the surface to be sampled by said surface sampler whilemaintaining the major portion of said tip portion slightly spaced fromthe surface and 5. collecting means detachably mounted within said coneassembly serving to retain samples removed from the surface beingsampled.

2. The vacuum surface probe sampler of claim 1 wherein said collectingmeans includes:

a IOU-mesh stainless steel screen carried by said head assembly andsupporting a membrane filter for collecting micro-organisms or the likewhen said vacuum probe surface sampler is passed over a test surfacearea.

3. The vacuum probe surface sampler of claim 2 wherein: a

said head portion is provided with an annular groove for receiving saidscreen and wherein the periphery of said screen is received by saidannular groove.

4. The vacuum probe surface sampler of claim 3 and further includinga'split retaining ring adapted to be received by said annular groove insaid head assembly to thereby retain said screen in position within saidhead assembly.

5. The vacuum probe surface sampler of claim 1 including an O-ring sealpositionable between engaging surfaces of said head assembly and saidcone assembly to provide a vacuum seal between these parts whenfriction-fitted together.

6. A vacuum probe surface sampler comprising:

a. a head assembly, and

b. a cone assembly detachably receiving said head assembly,

said head assembly being hollow and including an integrally attachedelongated tubular handle adapted to be grasped by an operator,

said tubular handle being attachable to a vacuum source at the free endthereof,

said cone assembly including an open cup-shaped portion and a basehollow cone portion integral with said cup-shaped portion,

said cone portion having an elongated tubular spout integrally extendingtherefrom,

said spout terminating in a flared substantially flattened open tip,

said flattened tip having an integrally attached pair of legs extendingtherefrom so as to maintain the major portion of said tip spacedslightly from a surface contacted by said legs during sampling of thesurface for micro-organisms or the like, and

means detachably within said cone portion for collecting and retainingsamples received from said surface being sampled.

1. A vacuum probe surface sampler comprising: I. a head assembly, a.said head assembly being cup-shaped and including an integrally attachedelongated tubular elongated tubular handle adapted to be grasped by anoperator,
 1. said tubular handle being connected to a vacuum source foroperation of said surface sampler, II. a cone assembly detachablyreceiving said head assembly, a. said cone assembly including a hollowfrusto-conical segment having an integrally attached cup-shaped baseportion and an elongated tubular spout,
 1. said cup-shaped base portionhaving a periphery thereof in the form of a tripod,
 2. said cup-shapedbase portion also serving to receive said head assembly with a notchedarea in said cup-shaped base portion receiving said tubular handle insuch position that when said head assembly is received by saidcup-shaped base portion that the entire head assembly will be verticallyspaced from the tripod periphery of said cup-shaped portion,
 3. saidtubular spout terminating in a substantially flattened open tip portion,4. a pair of leg members integral with said tip portion and adapted toengage the surface to be sampled by said surface sampler whilemaintaining the major portion of said tip portion slightly spaced fromthe surface and
 5. collecting means detachably mounted within said coneassembly serving to retain samples removed from the surface beingsampled.
 2. said cup-shaped base portion also serving to receive saidhead assembly with a notched area in said cup-shaped base portionreceiving said tubular handle in such position that when said headassembly is received by said cup-shaped base portion that the entirehead assembly will be vertically spaced from the tripod periphery ofsaid cup-shaped portion,
 2. The vacuum surface probe sampler of claim 1wherein said collecting means includes: a 100-mesh stainless steelscreen carried by said head assembly and supporting a membrane filterfor collecting micro-organisms oR the like when said vacuum probesurface sampler is passed over a test surface area.
 3. said tubularspout terminating in a substantially flattened open tip portion,
 3. Thevacuum probe surface sampler of claim 2 wherein: said head portion isprovided with an annular groove for receiving said screen and whereinthe periphery of said screen is received by said annular groove.
 4. Thevacuum probe surface sampler of claim 3 and further including a splitretaining ring adapted to be received by said annular groove in saidhead assembly to thereby retain said screen in position within said headassembly.
 4. a pair of leg members integral with said tip portion andadapted to engage the surface to be sampled by said surface samplerwhile maintaining the major portion of said tip portion slightly spacedfrom the surface and
 5. collecting means detachably mounted within saidcone assembly serving to retain samples removed from the surface beingsampled.
 5. The vacuum probe surface sampler of claim 1 including anO-ring seal positionable between engaging surfaces of said head assemblyand said cone assembly to provide a vacuum seal between these parts whenfriction-fitted together.
 6. A vacuum probe surface sampler comprising:a. a head assembly, and b. a cone assembly detachably receiving saidhead assembly, said head assembly being hollow and including anintegrally attached elongated tubular handle adapted to be grasped by anoperator, said tubular handle being attachable to a vacuum source at thefree end thereof, said cone assembly including an open cup-shapedportion and a base hollow cone portion integral with said cup-shapedportion, said cone portion having an elongated tubular spout integrallyextending therefrom, said spout terminating in a flared substantiallyflattened open tip, said flattened tip having an integrally attachedpair of legs extending therefrom so as to maintain the major portion ofsaid tip spaced slightly from a surface contacted by said legs duringsampling of the surface for micro-organisms or the like, and meansdetachably within said cone portion for collecting and retaining samplesreceived from said surface being sampled.